Role of land cover in Finland's greenhouse gas emissions

We present regionally aggregated emissions of greenhouse gases (GHG) from five land cover categories in Finland: artificial surfaces, arable land, forest, waterbodies, and wetlands. Carbon (C) sequestration to managed forests and unmanaged wetlands was also assessed. Models FRES and ALas were applied for emissions (CO₂, CH₄, N₂O) from artificial surfaces and agriculture, and PREBAS for forest growth and C balance. Empirical emission coefficients were used to estimate emissions from drained forested peatland (CH₄, N₂O), cropland (CO₂), waterbodies (CH₄, CO₂), peat production sites and undrained mires (CH₄, CO₂, N₂O). We calculated gross emissions of 147.2 ± 6.8 TgCO₂eq yr^-1 for 18 administrative units covering mainland Finland, using data representative of the period 2017-2025. Emissions from energy production, industrial processes, road traffic and other sources in artificial surfaces amounted to 45.7 ± 2.0 TgCO₂eq yr^-1. The loss of C in forest harvesting was the largest emission source in the LULUCF sector, in total 59.8 ± 3.3 TgCO₂eq yr^-1. Emissions from domestic livestock production, field cultivation and organic soils added up to 12.2 ± 3.5 TgCO₂eq yr^-1 from arable land. Rivers and lakes (13.4 ± 1.9 TgCO₂eq yr^-1) as well as undrained mires and peat production sites (14.7 ± 1.8 TgCO₂eq yr^-1) increased the total GHG fluxes. The C sequestration from the atmosphere was 93.2 ± 13.7 TgCO₂eq yr^-1. with the main sink in forest on mineral soil (79.9 ± 12.2 TgCO₂eq yr^-1). All sinks compensated 63% of total emissions and thus the net emissions were 53.9 ± 15.3 TgCO₂eq yr^-1, or a net GHG flux per capita of 9.8 MgCO₂eq yr^-1.